As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PRECISE FLIGHT STANDBY VACUUM SYSTEM FAILED TO OPERATE WHEN SELECTED. SUBSEQUENT INSPECTION REVEALED ACTUATION CONTROL CABLE TO BE LIMITED IN TRAVEL DUE TO INTERFERENCE WITH CONTROL VALVE LEVER. PREVIOUS EXPERIENCES WITH INSTALLING THIS SYSTEM HAVE FOUND THIS AREA TO BE TROUBLESOME TO ADJUST AND ALIGN. ANY MOVEMENT OF CABLE SUPPORT CLAMP CAN ADVERSELY AFFECT SYSTEM OPERATION.